Grate-bar



im, M, 1936. E. s, DILLEY 2,027,768

@RATE BAR Filed July l5, 1935 2 Sheets-Sheet l w, M QE MEEG//VG LINE.

Jam., M, w36. E', 5, DILLEY 2,@27368 GRATE BAR Filed July 15,1955 z'sn'eets-sheet 2 mi j .4M/f'V I MERE/NG Mms/Aie Patented Jan. 14, 1936 Uhil'i STATES FATEN' OFFCE Applieation .lul-ly 15,

4 Claims.

rlhis invention is a novel grate-bar and method of making same, said grate-bar being of the roclzing or shaking bar type, which undergoes a rather severe strain in the shaking or rocking operation, but can be applied to stationary or other type grates, the grate-bar' being particularly designed for use in locomotives.

The ideal heat resisting'metal for a grate-bar is of a gray-iron nature, commonly known as gray-iron, cast iron, or semi-steel but all of these metals are more or less brittle, and have a low resistance to shock. On the other hand metals of a malleable nature, such as steel, Whether cast or rolled, wrought iron, and annealed malleable iron, have a very high resistance to shock, and have a ductility not found to any appreciable extent in cast irons; but these latter mentioned metals will sag and warp if subjected to heat and in a short time, if not properly supported, will become so distorted that they will be rendered unserviceable. I have provided a dual cast grate-bar consisting of a combination of metals of the two above characteristics.

Will explain the invention with reference to the accompanying drawings which illustrate several embodiments thereof, and will summarize in the claims the essential novel features for which protection is desired.

Fig. l is a top plan view of a dual east gratebar of the pin hole type embodying my invention.

Fig. 2 is a side elevation thereof, and

Fig. 3 is a section on the line 3-3, Fig. l.

Fig. fi is a top plan view of a lringer-type form of grate-bar embodying my invention.

Fig. 5 `is a side elevation of the grate-bar shown in Fig. fi.

Fig. 6 is an end View of the grate-bar shown in Fig.

7 is a top plan view of a table-type form of grate-bar embodying my invention.

Fig. 8 is a side elevation of the grate-bar shown in Fig. 7; and

Fig. 9 is an end elevation of the grate-bar shown in Fig. 8.

My nevel grate-bar is preferably of cast metal, poured in a mold, and the form shown in Figs. 1-3 is of the pin hole type in which the finished bar is provided with a flat upper plate-like portion i usually of substantially rectangular shape, provided with series of staggered pin holes or perforations 2 therein for the draft of air therethrough in the usual manner. The grate-bar" may be provided at each end on its underside with a socket 3 for mounting the bar on the usual stub shafts or pins whereby the grate-bar may be rocked. Formed integrally with the underside of the grate-bar is a longitudinal central rib t, and depending therefrom is a rocker arno 5 (Figs. 1 and 2) which arm may be provided with the usual cross pin S at its lower end. Rib 4 is extended to meet the housings of the sockets 3. The underside of the grate-bar is also provided with integral longitudinal ribs l--l at its side edges, and provided with end ribs 8-6 connecting the ends of ribs l with the housings of the sockets 3, the ribs 4, l, S and socket housings 3 thereby supporting and reinforcing the upper plate-like portion i or" the grate-bar.

In constructing the grate-bar the mold (not shown) is made in the usual manner, and into the mold is iirst poured the molten cast steel, which as above stated is of a very malleable anid ductile nature. This cast steel is first poured into the mold until it nils the latter substantially up to the merging line a: shown in Figs. 2 and 3, the steel filling the cavity in the bottom of the mold which forms the rocker arm 5, and the cavities for the ribs il, l and 8, and the housings or sockets 3. The molten steel may also ll any other cavities which may be formed in the lower portion of a particular design of the grate-bar pattern.

After the mold is thus filled with molten cast steel to the line x, and before cast steel has an opportunity to become solidiiied, the upper portion of the mold, above the merging line x, is filled with molten gray-iron, east iron or semi-steel. The metals of the upper and lower portions of the grate-bar thereupon fuse together and make a perfect bond. The two metals do not and are not mixed in the gratebar but remain in their respective places in the mold and in the finished casting; however there is complete fusion between the two metals along the merging line x forming an integral dual cast grate-bar.

The cast iron of the upper plate portion of the grate-bar not only resists heat, but being relatively brittle also resists sagging and Warping and comes in direct contact with the fire whereas the cast steel which is disposed in the cooler portion of the nre-box and which does not come in direct Contact With the fire in the fire-box holds the upper portion in place even though the upper or cast iron portion may crack and break into several pieces. The combination of metals of the above natures, in the manner above described, therefore forms a perfect grate-bar.

The average expansion and contraction under heat (or what is known as shrinkage) for cast iron is 1/8" to the foot, while the average expansion and contraction (or shrinkage) for cast steel is to Mi" to the foot; and in my novel grate-bar the cast iron of the upper portion, which comes in contact with thergreatest heat has the lower co-eiiicient of expansion, while the cast steel of the lower portion, which lies in the cooler section of the fire-box has the higher co-efi'icient of expansion', yand thus in practical service these two co-eiiicients of expansion when subjected to the two different temperatures equalize the expansion and contraction of the entire grate-bar, thereby making it more serviceabie and less likely to crack, break or sag.

In Figs. 4, 5 and 5 the invention is illustrated in connection with a finger-type grate-bar having fingers I6 extending laterally from a center bar Il, which bar is provided on its underside with a longitudinally disposed rib I2; and adjacent one end of the grate-bar is a shaker arm i3 provided at its lower end with a cross pin or stud Ui, the shaker bar i3 being integral with the center bar li and rib i2. In forming this type of grate-bar the mold would be filled substantially up to the merging line y-y with molten steel (as above described in connection with the bar shown in Figs. 1-3 to include the shaker arm i3 and rib l2, and molten iron would then be poured into the upper portion of the mold to form the ash supporting finger portion of the grate-bar before the molten steel in the lower portion has solidified; and the two metals in their respective positions in the mold will fuse together along the merging line y-y, making a perfect bond.

In Figs. 7, 8 and 9 the invention is illustrated in connection with a grate-bar of the table type, in which the upper ash supporting portion of the grate-bar is substantially rectangular in plan and is provided with two parallel spaced longitudinal bars 2B and with integral spaced crossbars 2l, the cross-bars 2i extending as at 22 beyond the longitudinal bars 2%. In the ends of the upper portion are sockets 23, the housings of which are formed integrally with the longitudinal bars 23. The bars 2i as shown in Figs. 2 and 3 are substantially the saine depth as the housings for sockets 23.

At substantially the center of the grate-bar are a pair of shaker arms 26 which are integral with the longitudinal ribs 2li, both arms being cast on the bar, but the one not used may be subsequently broken off if desired.

In casting the grate-bars shown in Figs. 7, 8 and 9 the lower portion of the mold would be filled with molten steel up to the merging line e-z so that the shaker arms 24 and the lower portions of the longitudinal ribs 2i) and also of the cross-bars 2! and of the sockets 23 will be formed of cast steel; and before the molten steel has solidified the upper ash supporting portion of the mold is filled with molten iron, the two metals remaining in their respective places in the mold and in the finished casting, and fusing together along the merging line z-z and making a perfect bond.

I claim:-

l. A dual cast grate-bar comprising an ash supporting upper portion of metal oi a nature which will primariiy resist heat and sagging; and reinforcing ribs fused to the underside of the upper portion of metal of a nature having primarily a high resistance to shock.

2. A dual cast grate-bar comprising an ash supporting upper portion of metal of a nature which will primarily resist heat and sagging; reinforcing ribs fused to the underside of the upper portion; and a rocker arm extending from said ribs; the ribs and rocker arm being oi.' metal of a nature having primarily a high resistance to shock.

3. A dual cast grate-bar comprising an ash supporting upper portion of metal of a nature which will primarily resist heat and sagging; reinforcing ribs fused to the underside of the upper portion; socket housings at the ends of the upper portion having portions integral with the ribs; and a rocker arm extending from said ribs; said ribs, socket housing portions and rocker arm being of metal of a nature having primarily a high ductility and resistance to shock.

4. A dual cast grate-bar comprising an ash supporting upper portion of cast iron; reinforcing ribs on the underside of the upper portion; socket housings at the ends of the upper portion having portions integral with the ribs; and a rocker arm extending from said ribs; said ribs, socket housing portions and rocker `arm being of cast steel fused to the cast iron of the grate-bar.

EDWARD S. DILLEY. 

